with a list of spf.ciks observed. 229 



Order PULMONOBRANCHIA TA. 

 Fa M I Lv LIMN. £ID. -E. 



Planorbis nautileus, L. Local ; abundant l^etween Green- 

 hithe and Darenth Creek ; also few associated with Hydrobia 

 Jenkinsi, Plunistead Marshes. 



P. spirobis, Mull. Common ; and generally distributed. 

 P. vortex, L. Somewhat more local ; Tilbury Marsh. 

 P. carinatus, Mull. Local; near Abbey Wood. 

 P. complanatus, L. Common upon the Marshes both sides 

 of the river. 



P. corneus, L. Local. Specimens from the Marshes are not 

 generally so fine as those inhabiting the adjacent ponds and ditches. 

 P. contortus, L. Very local ; few from ditch, West Tilbury 

 Marsh. 



Physa hypnorum, L. A few shells in ditch upon Plumstead 

 Marshes. 



P fontinalis, Linn. Common ; and widely distributed. 

 \ar. infiata, Moq. Marsh near Abbey Wood Station. 

 Var. oblonga, Jeff. One specimen ; ditto, ditto. 

 Limnaea peregra, Mull. The commonest fresh water shell 

 upon the ^L\rshes. 



Var. ovata, Drap. Near Abbey Wood Station. 

 Var. acuminata, Jeff. Ditto, ditto. 



Var. labiosa, Jeff. Few specimens ; Plumstead Marshes. 

 Var. scalariforme, Jeff. Two shells only at Abbey "Wood. 

 L. stagnalis, L. Local ; a few at Purfleet ; also in pond 

 Shooter's Hill. 



Var. albida, Jeff. One shell ; Coldharbour Marshes, near 

 Purfleet. 

 L. palustris, Mull. Common ; everywhere. 

 L. truncatula. Mull. Scarce and local ; Plumstead and Rrith 

 ALarshes. 



Order PULMONIFERA. 

 Family ARIONID.E. 



At present I have recorded six species only of slugs from the 

 Marshes and immediate neighbourhood. 



Arion ater, L. (Black Slug.) Plumstead Marshes. One 

 specimen kept in captivity attained the length of 8^ inches when 



